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On Mon, 3 Jun 2002, Dan Brickley wrote: > ... A namespace document defines terms by > describing then in rdf/xml and/or in prose. Other documents, messages, > conference presentations etc might re-iterate or refine it. > > It seems reasonable for each rdf/xml term to have just one 'home' > namespace, alongside annotations about it from elsewhere. This is the > dominant model that people have used in deploying rdf/xml, I don't think I > know of any counter-cases. Dan, Roland, I'm not sure I "get it" yet... Let's suppose the "prose" document currently mirrored at http://www.gmd.de/People/Thomas.Baker/usage/terms/dc/ (to be installed at http://dublincore.org/usage/terms/dc/) is what I have been calling the "canonical" source of definitions -- that is, the document that gets edited after a Usage Board meeting and from which all other representations of DCMI semantics -- schemas, Web pages, "just-the-latest" excerpts, etc -- derive in a very practical, "workflow" sense. And let's suppose that Roland's RDF schema thereof is in effect derived from this "canonical" representation -- even if this simply means that someone is hand-checking the spelling and punctuation of the definitions between the angle brackets against the original "prose" document. In your terms, which document is the "namespace document" -- my prose (ie, flat-text) document or the RDF schema? Am I correct in understanding that your notion of "home" namespace (an identifier) is not the same as that of "namespace document" (a document)? > rdfs:isDefinedBy probably should have been called rdfs:ns, since we added > it to RDF Schema as a way of associating a term with the wider bundle of > names it was defined alongside. Given the specific way isDefinedBy is being used, that would work _alot_ better for me... On Fri May 31, Patrick wrote: >We need a way to relate a term to resources which define it. And >we should use rdfs:isDefinedBy (or a subproperty of it) to do this, >but that resource is not a namespace. It might be an RDF schema. >It might be an HTML instance with prose for humans. It might be >text. Whatever. This is why rdfs:ns would work alot better for me. If rdfs:isDefinedBy is being used (in effect) like rdfs:ns, it seems we might sometimes still need a pointer from an individual term declaration to a canonical source document (in this case, in "prose") in the form of something like the differently defined rdfs:isDefinedBy Patrick wants? In Roland's schema at http://www.mathematik.uni-osnabrueck.de/projects/dcqual/qual21.3.1/Schema/A/dcterms the arcs | <dc:source | rdf:resource="http://www.dublincore.org/documents/2000/07/11/dcmes-qualifiers/"/> | <dc:source rdf:resource="http://www.dublincore.org/usage/decisions/"/> point to a single source (prose) file for the entire RDF schema, as a whole. However, I should think that as the number of terms and related namespaces increases, such a document-oriented pointer -- from one RDF schema document to one prose document -- would become increasingly less useful for locating the "source" resources that define any particular term. Already in http://www.gmd.de/People/Thomas.Baker/usage/terms/dc/ the terms defined come from two namespaces -- as a document, it replaces both http://dublincore.org/documents/dces/ and http://dublincore.org/documents/dcmes-qualifiers/. And it is not difficult to imagine the more extreme cases Patrick (I believe) has in mind, where a schema uses terms from more than two namespaces. In the RDF schema of DCMI terms, then, might it not be helpful to have a pointer to the precise source of a definition in the canonical prose document, such as http://www.gmd.de/People/Thomas.Baker/usage/terms/dc/#title-003 (historically, the latest version of a term from the http://purl.org/dc/elements/1.1/ namespace) or http://www.gmd.de/People/Thomas.Baker/usage/terms/dc/#medium-002 (a term from the http://purl.org/dc/terms/ namespace)? Such precision might not be necessary in an informational RDF schema defining "just the current" elements in English for use in general-purpose RDF applications, as Roland is doing. But would such a pointer not be more important in an RDF schema of the elements defined in Japanese? How else would one point from a term declaration in Japanese back to the historically exact English wording upon which the translation was based? Would we not, then, need to ensure that each successive historical version of a term declaration has a unique identifier, such as http://dublincore.org/usage/terms/dc/#medium-002 or even http://purl.org/dc/terms/medium-002? Tom -- Dr. Thomas Baker [log in to unmask] Institutszentrum Schloss Birlinghoven mobile +49-171-408-5784 Fraunhofer-Gesellschaft work +49-30-8109-9027 53754 Sankt Augustin, Germany fax +49-2241-14-2619